In peace time, the US government used to spend very little on defense, about one percent of GDP. But that changed after World War II when the United States found itself in a global contest against Communism. Ever since, defense spending has never been less than 3.6 percent of GDP.ut 9/11, the terrorist attack on iconic US buildings in 2001, changed that, and defense spending began a substantial increase in two stages. First, it increased to 4.6 percent by 2005 for the invasion of Iraq, and then to 5.0 percent in 2008 for the the surge in Iraq.
The most noticeable difference is the sensation. A whirlpoolâs water jets come with the classic, high pressure, deep massaging jets that most people have come to associate with hydrotherapy. An air tub, on the other hand, is a more generalized, effervescent feeling.he most noticeable difference is the sensation. A whirlpoolâs water jets come with the classic, high pressure, deep massaging jets that most people have come to associate with hydrotherapy. An air tub, on the other hand, is a more generalized, effervescent feeling.
What this means though is the tub has an unused jet with stubbed off 3/4 hose connected, and a stubbed off hose on the manifold which comes after the hot tub pump and electric heater. The manifold has several tubes which direct water from the pump to the various jets which shoot water into the tub. My plan was to connect the stubbed ozone tubes to the tank heater in the basement and disconnect the electric heater. The hot tub sits at almost the same level as the base of the water heater. But I wondered whether the 5 foot tall heater if filled to the top would siphon into the tub and cause it to overflow. I therefore planned to fill the water heater only partway leaving an air cushion at the top.